• 한국문헌정보학회지
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• 제21권
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• pp.249-290
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• 1991

Theoretical developments in the information retrieval have offered a number of alternatives to traditional Boolean retrieval. Probability theory and fuzzy set theory have played prominent roles here. Fuzzy set theory is an attempt to generalize traditional set theory by permitting partial membership in a set and this means recognizing different degrees to which a document can match a request. In this study, an experimentation of a document retrieval system using the fuzzy relation matrix of the keywords is described and the results are offered. The queries composed of keywords and Boolean operaters AND, OR, NOT were processed in the retrieval method, and the method was implemented on the PC of 32bit level (30 MHz) in an experimental system. The measurement of the recall ratio and precision ratio verified the effectiveness of the proposed fuzzy relation matrix of keywords and retrieval method. Compared to traditional crisp method in the same document database, the recall ratio increased $10\%$ high although the precision ratio decreased slightly. The problems, in this experiment, to be resolved are first, the design of the automatic data input and fuzzy indexing modules, through which the system . can have the ability of competition and usefulness. Second, devising a systematic procedure for assigning fuzzy weights to keywords in documents and in queries.

• 농촌지도와개발
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• 제22권2호
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• pp.135-144
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• 2015

Competitiveness has been associated in the tourism literature as a crucial factor for the success of tourist destinations. This study is to develop indicators that measure destination competitiveness of rural tourism townships in Korea. It was conducted via a Delphi technique and the analytical hierarchy process method. After four rounds of discussions, the panel members reached consensus on a set of 27 indicators with three dimensions which are attractor (resource, infrastructure, and tourism products), assistance (tourism business assistance and value-added processing assistance), and planning and management (planning for development, capacity for management). This set of destination competitiveness indicators can serve as a starting point for devising a set of indicators at the local level in order to be useful rural tourism sector manager and administrators. The selected indicators are measurable, demand driven and practical to show the real performance in rural destination.

• ETRI Journal
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• 제27권6호
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• pp.713-724
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• 2005

This paper focuses on the problem of key-frames coding and proposes a new promising approach based on the use of fractals. The summary, made of a set of key-frames selected from a full-length video sequence, is coded by using a 3D fractal scheme. This allows the video presentation tool to expand the video sequence in a "natural" way by using the property of the fractals to reproduce the signal at several resolutions. This feature represents an important novelty of this work with respect to the alternative approaches, which mainly focus on the compression ratio without taking into account the presentation aspect of the video summary. In devising the coding scheme, we have taken care of the computational complexity inherent in fractal coding. Accordingly, the key-frames are first wavelet transformed, and the fractal coding is then applied to each subband to reduce the search range. Experimental results show the effectiveness of the proposed approach.

• 공학교육연구
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• 제27권4호
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• pp.21-27
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• 2024

This study introduces a series of processes aimed at understanding the noise characteristics generated by jet engines and devising measures to mitigate them through interdisciplinary capstone design projects. During the project execution, educational methods were applied to foster 4Cs (creativity, communication, collaboration, critical thinking) competencies. Project objectives were set through team discussions, and individual team members were assigned primary roles to act as subgroup leaders. As a result, the project was executed as follows: combustion tests were conducted using an SR-30 turbojet engine to generate noise, and the locations and characteristics of the noise sources were identified using beamforming techniques and frequency analysis applied to a 30-microphone array. Additionally, chevron nozzles were designed and fabricated to confirm their noise reduction performance.

• 아태비즈니스연구
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• 제14권4호
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• pp.413-429
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• 2023

Purpose - The purpose of this study is to investigate the determinants of consumers' inflation expectations using consumers' inflation perceptions and the sub-components of consumer price index (CPI) basket in South Korea based on a consumer survey conducted by the Bank of Korea (BOK). Design/methodology/approach - Using Carroll's (2003) epidemiological model, we analyzed data from January 2013 to January 2023, resulting in a data set of 121 observations for both inflation perceptions and inflation expectations. This study focuses only on aggregate inflation expectations and perceptions because of data availability from the BOK. Findings - Professionals' forecasts play a major role in forming consumers' inflation expectations, whereas the actual headline CPI and consumers' inflation perceptions do not. These results remain robust when including the sub-components of the CPI basket in the analysis. Research implications or Originality - It would be the most efficient way to suppress professionals' expected inflation in fighting against a substantial spike in consumers' inflation expectations. To guide consumers' inflation expectations based on BOK's inflation targeting, the bank needs to consider professionals' forecasts in devising monetary policies.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.693-698
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• 1991

This paper describes a fuzzy rule-based assembly algorithm for precision parts mating, The difficulties in devising reliable assembly strategies result from the complexity of the assembly process and the uncertainty such as imperfect knowledge of the parts being assembled as well as the limitations of the devices performing the assembly. To cope with above problems, we propose an assembly algorithm utilizing fuzzy set theory. The presented method allows us to represent the uncertainty by using fuzzy membership function and treat nonlinear sapping from measured force/torque to corrective motions using rules. Finally, the performance of this method is evaluated through a series of experiments. Experimental results show that the proposed method can be effectively used for chamferless and precision parts mating.

• 한국학교수학회논문집
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• 제14권2호
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• pp.163-178
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• 2011

2007년 개정 수학과 교육과정에는 학생들의 문제 해결력을 높이기 위하여 문제 만들기 활동 을 새롭게 추가하였다. 수학에서 문제 만들기와 문제해결은 함께하는 상호적인 작용으로, 교육 과정에 문제 만들기 활동이 구체적 제시되어 학생들의 문제해결력을 높이는 효과를 기대할 수 있다. 본 연구에서는 수학7의 대수영역을 중심으로 문제 만들기 문항을 수록한 16종의 교과서를 분석하였다. 문제 만들기 문항의 단원별 개수와 분포, 유형별 개수와 문항내용 등을 분석하였다.

• 한국과학예술포럼
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• 제19권
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• pp.259-267
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• 2015

Product-Service Systems (PSS) has drawn significant attention since it can effectively address diverse values of consumers by integrating products and services. PSS has been defined as a system of products, services, supporting networks and infrastructure that is designed to satisfy customer needs and to generate values. Manufacturing companies can accomplish business innovation by devising new service elements and providing PSSs starting from their products. Such new efforts are called manufacturing servitization. With analysis of the company's business contexts, diverse strategies could be set for servitization. Services could be developed so that their product functions can be supported. On the other hand, new services could be devised to drive active emotional values of their customers in a broadly related manner with their products. In this way, different servitization strategies in service space could be employed. In this paper, the product-service integration spaces for comparison of product-service systems in manufacturing servitization is briefly sketched. Various issue spaces, termed dimensions, would be used including service space, customer space, value space and business model space. Diverse PSS cases, including well-known PSSs and brand new PSSs, will be classified and compared to demonstrate the product-service integration spaces.

• 한국IT서비스학회지
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• 제5권3호
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• pp.121-135
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• 2006

With the growth and maturation of IT industry, the necessity of audit about development, maintenance and management of high-quality information system is gradually increasing. In addition, the necessity of inner auditing system, which could totally verify and evaluate the effectiveness of project according to the characteristics of organization conducting information-oriented business, also being proposed. Government offices including Korea Institute of Science and Technology(KISTI) collectively controlling nationwide science-technology related information have no guiding principle or organization within themselves even though performing information-oriented businesses are becoming more bigger and complicated. In this paper, we propose scheme for devising framework, which can audit construction and operation of knowledge information, check list and guideline. In addition, we present concrete ways for adapting these schemes to institutes which manage science-technology knowledge information. Audit framework consists of points of time in audit, audit domain and audit criterion. Points of time in audit are defined as three phases as followings: pre-audit, in-progress audit and post-audit. Audit domain includes 16 detail audit domains and especially we set 11 check items and 40 detail investigation items for database implementation business. We expect that management level of science-technology implementation business of organizations using this research result will increase and they could offer high-quality information service.

• 한국대기환경학회지
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• 제21권6호
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• pp.561-571
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• 2005

To introduce an emissions trading system for GHG that currently have no reduction requirements, the following should be considered as priorities: eliciting the participation of the industrial sector and linking GHG emission trading systems to the emissions trading system (implemented from July 2007) that has become part of national policy with the enactment of the Special Act. Two directions can serve as viable alternatives in that regard. One is a baseline-and-credit method based on incentive auctioning. This has the advantage of inducing participation through economic incentives without a reductions commitment. The downside of this method is that it requires vast investments, as well as the fact that reaching an agreement between participants and the government to decide an objective baseline is difficult. On the other hand, the cap-and-trade method set forth in the Special Act is attractive in that it can be integrated with the air pollutant emissions trading system, but it would be difficult to elicit the participation of the industrial sector in the absence of GHG emission reduction requirements. In the current situation, it would be preferable for the government to induce the participation of the industrial sector by devising a wide variety of incentives because taking part in the emissions trading system before reducing GHG emissions offers large incentives through learning by doing. The timing of GHG reduction commitments and emissions trading system implementation may be uncertain but their Implementation will be unavoidable. Thus the government needs to facilitate preparations for emissions trading of GHG in the future and continuously review its operation in integration with the air pollutant emissions trading system to maximize adaptation and teaming by doing effect in the industrial sector.